DESCRIPTION: The investigators propose a three-arm, randomized controlled trial of methods to improve adherence to biweekly directly observed prophylaxis (DOPT) for tuberculosis in homeless adults in San Francisco. The investigators propose to compare three approaches to improving adherence to biweekly DOPT in the homeless: $5 biweekly money incentive (MI) for adherence to DOPT, $5 value biweekly non-money incentive (NMI) for adherence to DOPT, and $5 biweekly money incentive supplemented by a peer community outreach worker (MI + PCOW). The outreach worker will assist subjects with completion of adherence to DOPT. Predictors of adherence to DOPT other than treatment arm, including sociodemographic, psychological and behavioral, and environmental factors, will be examined.